Comment on 'Effects of Particle Shape on Growth Dynamics at Edges of Evaporating Drops of Colloidal Suspensions'

摘要

Recently, Yunker et al. [1] reported an interesting experimental study on colloidal particle shape effects on edge growth for evaporating water drops, finding that kinetic roughening [2] of one-dimensional fronts of deposits depends on particle shape. In one of three regimes studied, particles with anisotropy 1.5 ≤ ε ≤ 3.5 induce roughness exponent values α_(loc) (＝) 0.61, β (＝) 0.68, argued to be compatible with the quenched Kardar-Parisi-Zhang (QKPZ) universality class. This QKPZ conclusion was supported by simulations of a discrete model [1], being found by the authors "unexpected," as quenched disorder was not the main experimental source of noise. Heterogeneous growth conditions were argued to originate it, via a "colloidal Matthew effect" (ME) by which particles adsorbing in particle-depleted regions are attracted to particle-rich regions, where they deposit preferentially.